Added script for launching nextcloud with kwallet

Source: https://github.com/nextcloud/desktop/issues/1011#issuecomment-510153674

scripts/nextcloud-kwallet.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+#
+# See https://github.com/nextcloud/desktop/issues/1011
+#
+############################################
+# Adjust the following to suit your needs
+WALLET="kdewallet"   # Name of wallet storing nextcloud client password
+MAX_TRIES=2          # Max. number of tries to ask for password
+############################################
+i=0
+while [ $i -lt $MAX_TRIES ]; do
+  ((i++))
+  open=`qdbus org.kde.kwalletd5 /modules/kwalletd5 isOpen "$WALLET"`
+  if [ "$open" = "true" ]; then
+    break
+  fi
+  qdbus org.kde.kwalletd5 /modules/kwalletd5 open "$WALLET" 0 "nextcloud-client-starter" > /dev/null
+done
+nohup nextcloud >> /dev/null 2>&1